Placental EPO mRNA Expression Is Measurable in Very Preterm to Term Placentae

Abstract

ObjectivesOur objective was to evaluate placental EPO mRNA expression in term and preterm placentae and explore maternal/neonatal/placental determinants of EPO expression. MethodsPlacental tissue was collected from pregnant adolescents (n = 82, < 19 y of age) and from women (n = 62) carrying multiple fetuses (twins = 23, triplets = 39). Placental mRNA expression was evaluated using qPCR. Hemoglobin and iron status biomarkers (SF, TBI, sTfR, Hepcidin) were measured in maternal blood at delivery and in cord blood. ResultsIn this population, women delivered between 30–42 weeks of gestation. Of the 144 women, 30% delivered prematurely (< 37 weeks, n = 44) and 69% delivered at term (≥37 weeks, n = 100). As expected, preterm placentae weighed significantly less than term placenta (293 ± 93 g vs. 544 ± 143 g, p < 0.0001). Placental EPO mRNA expression was detected in all samples collected. Placental EPO mRNA expression did not significantly differ between anemic (Hb < 13 g/dL) (n = 23) and non-anemic (n = 84) neonates (p = 0.69), nor was it significantly associated with maternal anemia at delivery (p = 0.44). Placental EPO mRNA expression was also not significantly associated with maternal (p = 0.56) or neonatal (p = 0.61) Hb concentrations, placental weight (p = 0.46) or gestational age at delivery (p = 0.39). ConclusionsWhile placental EPO mRNA was detected in all placental tissue collected between 30–42 weeks of gestation none of the iron biomarkers evaluated were significantly related to placental EPO mRNA expression. Further studies are needed to understand determinants of placental EPO mRNA and protein expression. Funding SourcesThe U.S. National Institutes of Health (NIH) National Institute of Child Health and Development (NICHD) Grant 1R21HD098864, The Gerber Foundation and USDA grants 2005–35,200-15,218 and 2009–35,200-05,171.